What is is?
Prostate specific antigen is a protein manufactured exclusively by the prostate gland.
How does it work?
This antigien is present at low levels (0-4.0 ng/mL) in the blood serum of healthy men. However, increased levels of this antigen are present in the blood of an individual with prostate cancer.
This discovery has lead to a simple blood test effectlivly being used in the early detection of prostate cancer.
- PSA levels of less than 4 ( may vary with age ) are considered normal
- it is important to note that prostate cancer may exist even with PSA levels in the normal range.
- PSA levels over 4 may be considered elevated and may indicate benign disease or prostate cancer.
- The higher the PSA level, the more likely the presence of cancer.
- This test may be routinely used to detect prostate cancer in men over 50
- Men at a higher risk of prostate cancer or with a family history of prostate cancer may wish to consulting their family physician about this test to begin screening when they are 40-45 years old.
The BC Cancer Agency. 2009. Prostate Cancer. Retrived June 26, 2009 from http://www.bccancer.bc.ca/PPI/Screening/Prostate.htm
The US National Cancer Insitite. 2009. Prostate Specific Antigen (PSA) Test. retrieved June 26, 2009 from http://www.cancer.gov/cancertopics/factsheet/Detection/PSA/print?page=&keyword=